Outlook2000

Outlook suffers from many vulnerabilities. A majority of worms and virus' target Outlook. Be sure to install the security updates. There are many security issues with Outlook. Apply service pack 2 for office 2000 and this will take care of the currently known issues.

I provided a link for the update below...

http://www.microsoft.com/office/ork/2000/journ/OffSP2.htm?FinishURL=%2Fdownloads%2Frelease%2Easp%3FReleaseID%3D26102%26area%3Dsearch%26ordinal%3D13%26redirect%3Dno

Outlook has many problems.
The obvious is the executables that contain viruses that will take advantage of Outlook and send itself to everyone in your Outlook address book.
But you don't necessarily have to open an attachment in Outlook to be infected. Outlook has a "Preview" vulnerability.
Microsoft has released many patches to combat it's vulneribilities. But be aware that some may limit your abilities. It is sometimes all or none with MS. One such update will block attacments that haveextensions of programs known to be virus freindly. But it blocks a lot of attacments that may be legitimate and it doesn't allow you to view or save them.
I would defineately heed the advice prior, and read about Outlook on the MS website.